Sometimes the measurement seems irrelevant to the user experience, even if it has a good diffusion index.

It shows 3 units less compared to others. Which one is correct, I don't know as there is no other reliable reference device...

This particular oximeter comes in about 10 variations (the last letter of the code changes, JPD-500D). It is also rebranded and sold under 20-30 different names, at various prices. The cheaper models (8-10€) differ from the more expensive ones (15+) in terms of the screen, with monochrome LED instead of color OLED with a rotating display indication (instead of a fixed one). The indications and accuracy, based on the manufacturer's certifications, are exactly the same for all of them. They all use 2 AAA batteries. It comes with a case and a strap for hanging on the hand.

In conclusion, if you find a model with a color screen for around 15€, prefer it regardless of the brand, because it also has slightly better construction in the plastic clip that holds the finger. Otherwise, go for the cheaper one.

Easy to use, it does exactly what it was designed for. With 2 weeks of operation, for 2 people using it 4-5 times a day, its batteries work very well. It may be unnecessary, but when we needed it, it served us very well in the illness we went through.

I bought it because I often get sick due to an autoimmune problem, and my doctor recommended it to me to assess my condition and prevent me from going to the hospital on time

I have no prior knowledge and cannot compare it to other products. From what I know, the correct measurement is always done with the index finger of the left hand. When I try consecutive measurements on the same person, it always gives the same result, so I consider its measurements to be reliable.

It does not have internal instructions. If you hold down the on-off button, it enters its settings.

A fairly affordable, but reliable oximeter. Of course, there are better ones, but you have to pay a lot more money for them. It was measured with another oximeter as well as with a smartwatch and its readings were almost identical. +/- 1 less or more and many times the same. I would recommend it for purchase to others. In terms of quality, it could have been more sturdy, but let's not forget the price. Basically, we are interested in the measurements, which in this case were accurate.

Satisfied! It is very reliable!
I checked it with my pulses, which I know due to the blood pressure monitor, how many are at rest, standing, and walking. I also compared it to another oximeter.
It is very bright in indications, showing the pulse waveform live on the color screen,
it shows battery level (batteries included!) and has warning alarms for anything that goes wrong in the measurement, within the limits of good health.
Although the prices of many oximeters have increased significantly recently, the JUMPER is affordable and worth its money!
Guaranteed!
I recommend it!